Results 1 to 12 of 12
  1. #1
    mtbr member
    Reputation:
    Join Date
    Dec 2009
    Posts
    59

    Dilema rd or mtb powertap hub for Mtbiker

    Hello guys, having a dilema over here. Have the cash to buy a powertap. I'm mainly a mtbiker racer. As I said I'm planning to bauy a powertap. I have rdbike on wich I do a lot of training from long endurance to intervals. But I also do a lot of training on my 29er. My question is this, should I buy a rdb hub or a mtb powertap hub. I was convinced to buy a rdb hub, but I will not be able to collect mtb race data, wich I find very important, or I can make sound improvement without race data?
    Help guys.

    Mtbiker3995

  2. #2
    mtbr member
    Reputation: Poncharelli's Avatar
    Join Date
    Jan 2005
    Posts
    2,182
    I would check your current weekly RB hours vs. MTB hours.

    Go powertap with which ever is much greater.

    It's easier for me to hit the road versus the trail, so I always log more road time, especially via bike commuting. Also, structured riding is just much easier on the road, which is the point of a PM I believe (structured training).

    I like not having a PM on the MTB. MTB time is fun time for me. The last thing I want when shredding some singletrack is to get caught up with numbers.
    Head Coach, Ben Lomond HS MTB Team
    www.utahmtb.org
    Cycling Team and local Club:
    http://www.roostersbikersedge.com/

  3. #3
    mtbr member
    Reputation:
    Join Date
    Dec 2009
    Posts
    59

    WR304 help

    Tnx poncharelli.

    WR304 can you help me please.






    mtbiker3995

  4. #4
    mtbr member
    Reputation: WR304's Avatar
    Join Date
    Jul 2004
    Posts
    3,600
    I use my mountain bike for both on and offroad rides. The only difference being that I pump the tyres up to 50psi for road use. Unless you're riding with other people speed doesn't matter, especially if you're aiming for a particular wattage. If you have to choose between two bikes then it really depends what you want the powertap for.

    If it's to look at how you're riding offroad then the mtb version would be the one to go for. I was quite shocked at just how scruffy my typical offroad rides were - lots of freewheeling, soft pedalling and stationary time. I knew I was slower offroad than onroad but put that down to the terrain. I had always thought that my mountain bike rides were similar in intensity to a steady road ride overall. The power meter showed that clearly wasn't the case. From there I was able to identify the weakest areas and try to pedal harder at those points.

    At the same time I was putting in short sharp efforts offroad in particular sections without appreciating quite how far above threshold they were. Riding over rough ground is hard work. One of the most significant things to come from that was the realisation that having the suspension on my Specialized Epic with a lot of platform was proving counter productive. I was actually faster for the same wattage with softer suspension settings. Being able to look at speed vs wattage with different tyres on different surfaces is another area that I found helpful. The results weren't what I'd have expected there either. There are some links and offroad power data in this thread:

    MTB power meter thread.

    If you mainly want to use the power meter as a training tool for pacing your intervals and maintaining a constant pace on long rides then having it on the road bike could be best. On the road it takes practice but you can use the power meter to gauge your effort effectively over longer durations. This link shows how it should be done. Much better than I manage.

    Analysis of Jordan Rapp's Ironman Texas Performance - Quarq Blog

    Being able to do an "apples to apples" comparison of power for your intervals gives an indication of whether you're improving, and also whether you're pacing them correctly. Intervals such as over-under intervals where you're changing intensity multiple times can be hard to get right. The power meter takes some of the guesswork out.

    LTHR Test Findings, Need Help

    With the growing popularity of disc brake road and cyclocross frames the other option would be to get a mtb powertap and switch it between bikes. Built into a 29er (700c) rim you could use the same wheel on both a disc brake road bike and a 29er mountain bike, only needing to swap tyres.
    Last edited by WR304; 09-15-2012 at 06:51 AM.

  5. #5
    mtbr member
    Reputation:
    Join Date
    Nov 2009
    Posts
    501
    One thing to keep in mind, road bikes are looking like they are going to be getting disc brakes soon and moving to 135mm spacing to make room for the rotor. The MTB powertap may just become the disc brake power tap. No one has said for sure though.
    Last edited by litany; 09-15-2012 at 02:56 PM.

  6. #6
    mtbr member
    Reputation:
    Join Date
    Dec 2009
    Posts
    59
    Thx guys, apreciate your contribution. I'll order the disc version.


    Mtbiker3995

  7. #7
    dcb
    dcb is offline
    mtbr member
    Reputation:
    Join Date
    Sep 2005
    Posts
    261
    Another option would be the powertap for the mtb bike and a Powercal for the road bike. I read a review that said its pretty consistent with a powertap especially during steadier efforts.

  8. #8
    mtbr member
    Reputation: WR304's Avatar
    Join Date
    Jul 2004
    Posts
    3,600
    Some quick notes for when you get a Powertap.

    - Unscrew the battery compartment's plastic cover and put some waterproof marine grease around the rubber seals to help keep water out.
    - Put some light grease on the freehub pawls, clean and regrease them frequently (every 1-2 months) to keep the freehub engaging smoothly. The freehub is tool free so you can pull it off by hand.
    - Replace the batteries every 100 hours or so of riding. You don't get a low battery warning if you have a Garmin head unit so it's best to do it before they go flat.
    - Measure the compressed circumference of the tyres you intend to use when you're actually riding the bike. If you keep the measurements in a spreadsheet you can easily change the setting in the head unit to match your tyres. Because the Powertap uses the rear wheel circumference any printed tyre tables will be inaccurate.
    - Newer Garmin firmware allows you to have the display as 10 second smoothing. This makes the display less jumpy and is easier to pace yourself with than instant power.
    - If you add manual lap markers to your data it makes it easier to understand, allowing you to work out where you were at particular points when looking through the ride file post ride on computer. A long ride without any lap markers or notes is much harder to interpret.

  9. #9
    mtbr member
    Reputation:
    Join Date
    Dec 2009
    Posts
    59

    paired to a Garmin edge 500

    I'm planning to pair the powertap with a Edge 500. You mention the new firmware. I've heard that the 3.0 update has some glitches, some people are back to 2.8. Didi You had this problem? (WR304)



    MTbiker3995

  10. #10
    mtbr member
    Reputation:
    Join Date
    Nov 2009
    Posts
    501
    Quote Originally Posted by mtbiker3995 View Post
    I'm planning to pair the powertap with a Edge 500. You mention the new firmware. I've heard that the 3.0 update has some glitches, some people are back to 2.8. Didi You had this problem? (WR304)



    MTbiker3995
    I haven't noticed any problems with the newest firmware on my garmin edge 500 with either my mtb power tap or my mtb quarq.

  11. #11
    mtbr member
    Reputation: WR304's Avatar
    Join Date
    Jul 2004
    Posts
    3,600
    I haven't had any issues with the newest Garmin Edge 500 firmware. There are some very specific Garmin Edge 500 features (such as GPS courses and autopause) which can cause problems. So long as you avoid using those features the Garmin Edge 500 head unit ought to be trouble free.

    These are my Garmin Edge 500 settings for use with a Powertap hub:

    PowerTap Disc

    The only outdated part of that post is the display settings. Now that 10 second smoothing is available for the display I use that instead of 3 second smoothing whilst riding.

  12. #12
    mtbr member
    Reputation:
    Join Date
    Dec 2009
    Posts
    59
    thx WR304
    I've ordered the hub today, its the 2012 pro version, will be laced to a WTB I23 29er rim.
    When its ready I'll post some pictures.

    Mtbiker3995

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •